%hyla%

n. fld>(Med.) Shock resulting from anaphylaxis{ 2 }. It is a severe form of physiological shock, often having a fatal outcome, and is caused by an extreme immunological reaction to antigens. It is characterized by smooth muscle contraction and capillary dilation throughout the body, initiated by antibodies of the IgE class. It is usually seen when an antigen to which a person has become hypersensitized is injected intravenously or subcutaneously. It is also called generalyzed anaphylaxis or systemic anaphylaxis, and sometimes anaphylaxis. [ Stedman ] [ PJC + AS ]

n. sn>1. [ Gr. 'ana` back, way from + fy`laxis security, protection. ] 1. (Med.) Hypersensitivity (to a foreign antigen) resulting from prior contact with the same or a related substance. [ WordNet 1.5 + AS ]

2. (Med.) An immediate but transient systemic reaction to an antigenic substance to which a person has become hypersensitized; it is characterized by the contraction of smooth muscle and capillary dilation. [ Stedman ] [ PJC + AS ]

The cascade of events is triggered by binding of the foreign antigen to immunoglobulin E and release of mediators such as histamine, bradykinin, serotonin, and slow-reacting substance from mast cells. It involves more than one organ system. The most commonly involved organs are skin, cardiovascular, respiratory and gastrointestinal systems. Anaphylaxis is manifested by a range of signs and symptoms including pruritus, urticaria, itching, dyspnea, abdominal pain and cardiovascular collapse (shock). A severe form of the reaction is called anaphylactic shock. [ Stedman ] [ PJC + AS ]

3. (Med) Anaphylactic shock. [ AS ]

a. (Physiol.) Possessed of the properties of chyle; consisting of chyle. [ 1913 Webster ]

a. [ Chyle + aqueous. ] (Zool.) Consisting of chyle much diluted with water; -- said of a liquid which forms the circulating fluid of some inferior animals. [ 1913 Webster ]

{ , a. [ L. conchylium shell, Gr. &unr_;, dim. of &unr_;, equiv. to &unr_;. See Conch. ] Of or pertaining to shells; resembling a shell; as, conchyliaceous impressions. Kirwan. [ 1913 Webster ]

n. [ Pref. di- + ethylamine. ] (Chem.) A colorless, volatile, alkaline liquid, NH(C2H5)2, having a strong fishy odor resembling that of herring or sardines. Cf. Methylamine. [ 1913 Webster ]

n. [ Ethyl + amine. ] (Chem.) A colorless, mobile, inflammable liquid, C2H5.NH2, very volatile and with an ammoniacal odor. It is a strong base, and is a derivative of ammonia. Called also ethyl carbamine, and amido ethane. [ 1913 Webster ]

n. [ From Ethyl. ] (Chem.) A compound derived from ethyl alcohol by the replacement of the hydroxyl hydrogen, after the manner of a hydrate; an ethyl alcoholate; as, potassium ethylate, C2H5.O.K. [ 1913 Webster ]

v. t. [ imp. & p. p. Ethylated; p. pr. & vb. n. Ethylating. ] [ From Ethyl. ] (Chem.) To treat in such a way as to cause the introduction of one or more ethyl groups, C2H5-; as, to ethylate alcohol. [ Webster 1913 Suppl. ]

{ ‖ } n. [ NL. hylaeosaurus, fr. Gr. &unr_; belonging to a forest (fr. &unr_; wood) + &unr_; a lizard. ] (Paleon.) A large Wealden dinosaur from the Tilgate Forest, England. It was about twenty feet long, protected by bony plates in the skin, and armed with spines. [ 1913 Webster ]

a. [ Gr. &unr_; wood, matter + &unr_;: cf. F. hylarchique. See Archical. ] Presiding over matter. [ Obs. ] Hallywell. [ 1913 Webster ]

n. [ Methylene + alcohol. ] (Chem.) A light, volatile liquid, H2C(OCH3)2, regarded as a complex ether, and having a pleasant ethereal odor. It is obtained by the partial oxidation of methyl alcohol. Called also formal. [ 1913 Webster ]

n. (Chem.) See Methyl amine, under Methyl. [ 1913 Webster ]

n. [ Methyl + alcoholate. ] (Chem.) An alcoholate of methyl alcohol in which the hydroxyl hydrogen is replaced by a metal, after the analogy of a hydrate; as, sodium methylate, CH3ONa. [ 1913 Webster ]

v. t. To impregnate or mix with methyl or methyl alcohol. [ 1913 Webster ]

a. (Chem.) Impregnated with, or containing, methyl alcohol or wood spirit; as, methylated spirits. [ 1913 Webster ]

n. (Chem.) One of two basic amido derivatives of naphthalene, C10H7.NH2, forming crystalline solids. [ 1913 Webster ]

n. (Chem.) A salt of oenanthylic acid; as, potassium oenanthylate. [ 1913 Webster ]

n. [ Oxamic + methyl. ] (Chem.) Methyl oxamate, obtained as a pearly white crystalline substance. [ 1913 Webster ]

n. A phylactery. Sandys. [ 1913 Webster ]

a. Wearing a phylactery. [ 1913 Webster ]

{ } a. Of or pertaining to phylacteries. [ 1913 Webster ]

n.; pl. Phylacteries [ OE. filateri, OF. filatire, filatiere, F. phylactère, L. phylacterium, Gr. fylakth`rion, fr. fylakth`r a watcher, guard, fyla`ssein to watch, guard. Cf. Philatory. ] 1. Any charm or amulet worn as a preservative from danger or disease. [ 1913 Webster ]

2. A small square box, made either of parchment or of black calfskin, containing slips of parchment or vellum on which are written the scriptural passages Exodus xiii. 2-10, and 11-17, Deut. vi. 4-9, 13-22. They are worn by Jews on the head and left arm, on week-day mornings, during the time of prayer. Schaff-Herzog Encyc. [ 1913 Webster ]

3. Among the primitive Christians, a case in which the relics of the dead were inclosed. [ 1913 Webster ]

n. [ Gr. fyla`ssein to guard + karpo`s fruit. ] (Zool.) A branch of a plumularian hydroid specially modified in structure for the protection of the gonothecæ. [ 1913 Webster ]

{ ‖‖ } n. pl. [ NL., fr. Gr. fyla`ssein to guard + laimo`s the gullet. ] (Zool.) An order of fresh-water Bryozoa in which the tentacles are arranged on a horseshoe-shaped lophophore, and the mouth is covered by an epistome. Called also Lophopoda, and hippocrepians. [ 1913 Webster ]

a. (Zool.) Of or pertaining to the Phylactolæma. [ 1913 Webster ]

{ ‖‖ } n. pl. [ NL. ] (Zool.) Same as Phylactolæma. [ 1913 Webster ]

n. [ L. phylarchus, Gr. &unr_;. See Phyle, and -arch. ] (Gr. Antiq.) The chief of a phyle, or tribe. [ 1913 Webster ]

n. [ Gr. fylarchi`a. ] The office of a phylarch; government of a class or tribe. [ 1913 Webster ]

n. [ Cf. F. prophylactique. ] (Med.) A medicine which preserves or defends against disease; a preventive. [ 1913 Webster ]

{ , a. [ Gr. &unr_;, fr. &unr_; to guard against; &unr_; before + &unr_; to guard: cf. F. prophylactique. ] (Med.) Defending or preserving from disease; preventive. Coxe. [ 1913 Webster ]

‖n. [ NL. See Prophylactic. ] (Med.) The art of preserving from, or of preventing, disease; the observance of the rules necessary for the preservation of health; preservative or preventive treatment. [ 1913 Webster ]

‖n. pl. [ NL., fr. Gr. sy`n with + &unr_; a clan. ] (Zool.) An order of small apterous insects having an elongated body, with three pairs of thoracic and about nine pairs of abdominal legs. They are, in many respects, intermediate between myriapods and true insects. [ 1913 Webster ]

n. [ Gr. &unr_; a sack. ] (Zool.) The zebra wolf. See under Wolf. [ 1913 Webster ]

n. [ Pref. tri- + ethylamine. ] (Chem.) A tertiary amine analogous to trimethylamine. [ 1913 Webster ]